Operating material supply device

ABSTRACT

The invention relates to an operating material supply device for hydrodynamic components, in particular hydro-dynamic switching elements in starting units, retarder assemblies or gearing assemblies, having an operating material reservoir which is arranged in the housing of the starting unit or retarder unit or gearing assembly and comprises an operating material sump with at least one filling line which connects the operating material sump to the hydrodynamic component. The invention is characterized by the following feature: the operating material sump can be closed in a pressure-tight manner.

[0001] The invention relates to an operating material supply device forswitchable elements, in particular hydrodynamic components in startingunits, retarder units or gearing assemblies, specifically having thefeatures from the pre-characterizing clause of claim 1.

[0002] Hydrodynamic components in starting units, retarder units orgearing assemblies can be of switchable design, this presupposing thatthere is the possibility of filling and emptying them. There isincreasingly the requirement here for rapid chilling. For example, whenhydrodynamic constructional units are designed in the form ofhydrodynamic retarders, very short filling times are required for safetyreasons, in order to achieve a rapid breaking action or a regulatedtorque profile which, for example, is intended to cause a certain speedprofile when starting up an engine. According to general designs knownthrough use in the prior art, the filling takes place with the aid ofoperating material reservoir devices which use external auxiliary powerfrom the vehicle or from their own force to accelerate the fillingprocess when hydrodynamic elements are being filled. In this case, useis made, for example, of piston-type reservoirs which are actuated byspring force or compressed air from the compressed air system of thevehicle. A further possibility is to set the entire housing space underpressure and, as a result, to press operating material out of the oilsump into the corresponding, hydrodynamic component. Other filling aidsconsist in using corresponding pump devices.

[0003] However, the designs according to the prior art have thedisadvantage of being very power-consuming in terms of the conversionand of presupposing special equipment.

[0004] The invention is therefore based on the object of developing anoperating material supply device for switchable elements of startingunits, retarder units or gearing assemblies in such a manner that thedisadvantages mentioned are avoided. Specifically, the focus is to be onrealizing particularly short filling times and, if compressed air isused as the pressure medium, the consumption of air is to be as small aspossible and is to take place effectively. Furthermore, the operatingmaterial supply device designed according to the invention is not topermit any impairment with regard to its function and hence also withregard to the function of the switchable element or elements even in thecase of repeated, rapidly successive actuations. The structural outlayis to be kept low and the cost expenditure is to be kept minimal.

[0005] The solution according to the invention is characterized by thefeatures of claim 1. Advantageous refinements are reproduced in thesubclaims.

[0006] The operating material supply device for switchable elements, inparticular hydrodynamic components in starting units and gearingassemblies, comprises an operating material reservoir having anoperating material sump arranged in the housing of the corresponding,switchable element or of the overriding starting, retarder or gearingassembly. Said operating material sump is connected to the switchableelement, in particular the hydrodynamic component, via at least onefilling line. According to the invention, the operating material sumpcan be closed in a pressure-tight manner with respect to the remainingpart of the operating material reservoir or the housing of theswitchable element, in particular the hydrodynamic component or anoverriding starting unit, retarder unit or gearing assembly, for whichpurpose corresponding means for the pressure-tight closure of theoperating material sump with respect to the surroundings or the housinginterior are provided. In order to bring about a rapid fillingoperation, means for charging the operating material in the operatingmaterial sump with an influencing pressure are provided.

[0007] The solution according to the invention offers the advantage ofsimple filling by means of pressure medium with a free configuration ofthe geometrical shape and dimensions of the operating material sumpwhich enables the design of the operating material supply system to beoptimally adapted to the available structural space. A further advantageresides in the provision of the largest possible reservoir volumes andin a small consumption of pressure medium, since only the operatingmaterial volume in the operating material sump, as a rule the oil sump,is sealed while the remaining part of the operating material reservoirremains vented. Switching operations taking place rapidly one behindanother are not impaired, since oil flowing out of the hydrodynamicelements when switching off takes place is returned directly into thesump. In this case, the operating material sump is used both foroperating material flowing back from switching elements and also fromhydrodynamic components.

[0008] There are a multiplicity of possibilities for the actualstructural design of the means for the pressure-tight closing of theoperating material sump with respect to the surroundings or the housinginterior and the means for charging the operating material sump with aninfluencing pressure. In order to bring about rapid filling operations,said means are functionally coupled to each other. Furthermore, astructural coupling preferably takes place, with at least individualcomponents preferably being part of both.

[0009] The means for the pressure-tight closure of the operatingmaterial sump with respect to the surroundings or the housing interiorcomprise at least one control valve having at least one valve elementwhich interacts with a valve seat, which is formed by the elementforming the opening, and a movable piston element which is coupled tothe valve element. The control valve is coupled to an actuating devicefor actuating the valve element. Said actuating device connects apressure connection to the pressure chamber. The means for producing aninfluencing pressure also comprise a valve device which, when chargedvia an actuating device, connects a pressure medium connection or aconnection to the atmosphere to the operating material sump. Accordingto a particularly compact design, the control valve of the means for thepressure-tight closure and the valve device for coupling the atmosphereor a pressure medium connection to the operating material sump arecombined in a combined valve device. Furthermore, the actuating devicefor the control valve and the valve device is formed by an actuatingdevice assigned jointly to both. The combined valve device comprises atleast one pressure space in which the valve element of the control valveand the valve element of the second valve device of the means forcharging with pressure are arranged and mounted displaceably, and aconnection to the atmosphere or to a pressure medium source and afurther, second connection to the operating material sump. The valveelements of the valve device of the charging means and of the controlvalve are kept in a prestressed position in the unpressurized state bymeans of spring devices. The corresponding dimensioning of the springdevices and of the charging surfaces on the piston elements forming thevalve elements make it possible here for the closure of the operatingmaterial sump and the filling to be functionally coupled withoutadditional control measures.

[0010] A particularly advantageous use of the solution according to theinvention resides in the possibility of being coupled to a closed,pressure-tight circuit assigned to the hydrodynamic component.

[0011] There are no restrictions with regard to the sphere of use. Usesboth in the vehicle and in stationary systems are possible.

[0012] The solution according to the invention will be explained belowwith reference to figures, in which the following is illustratedspecifically:

[0013]FIG. 1 illustrates an operating material supply device designedaccording to the invention in the unpressurized state;

[0014]FIG. 2 illustrates an operating material supply device designedaccording to the invention during the closing of the operating materialsump;

[0015]FIG. 3 illustrates an operating material supply device designedaccording to the invention when being charged with pressure.

[0016]FIG. 1 illustrates an operating material supply device 1 designedaccording to the invention for switchable elements in starting, retarderand/or gearing assemblies. The switchable elements are preferablyhydrodynamic components in the form of hydrodynamic clutches,hydrodynamic brakes or hydrodynamic speed/torque converters. Theoperating material supply device 1 comprises an operating materialreservoir 2 having an operating material sump 3. The operating materialsump is coupled to the switchable element, in particular to a workingspace of a hydrodynamic component, via at least one filling line 4.Furthermore, a suction line 36 of an oil supply pump is provided. Theoperating material reservoir 2 is arranged in a housing. Said housing isa housing of the switching element, of the starting unit, retarder unitor of the gearing assembly. The operating material reservoir 2 comprisesa housing 5 which is preferably formed by the housing 32 of theswitchable element, of the starting unit or retarder unit or of thegearing unit. In a particularly compact configuration, when theoperating material supply device 1 is assigned to a hydrodynamiccomponent, the housing 5 of the operating material reservoir 2 is formedby the housing of the hydrodynamic component. According to theinvention, the operating material sump 3 is of closable design. Thisfunction is realized via means 6 for the pressure-tight closure of theoperating material sump with respect to the surroundings or the housinginterior 33 in which the operating material reservoir 2 is situated. Theoperating material sump 3, and thus also the operating materialreservoir unit 2, is always arranged with respect to the switchableelement in such a manner that the latter is arranged below the operatingmaterial level 7, that is to say, generally below the oil level in theoperating material reservoir 2. The operating material sump 3 isenclosed by a housing wall region 8 which lies below the operatingmaterial level 7 usually present in the switchable element or thehousing 32 of the switchable element or its overriding unit. The housingwall region 8 here forms a chamber 9 which can be filled with operatingmaterial and which has at least one opening in the upper region on theupper boundary wall 10 in the installed position. The opening isreferred to here by 11. The means 6 for the pressure-tight closure ofthe operating material sump 3 with respect to the surroundings or therest of the housing interior of the operating material reservoir 2 or,when this housing 5 is formed from the housing of the switchable elementor of the gearing assembly or of a starting element, with respect to thehousing interior 33 thereof comprise a device 12 for closing the opening11. This device comprises a control valve 13, the valve element 14 ofwhich is formed by a movable piston element 13 which enters intooperative connection with a valve seat 16 which is formed by the opening11. For this purpose, the valve element 14 can be charged with pressuremedium, specifically via an actuating element 17 for actuating the valveelement 14, in the case illustrated in the form of a valve device 18,which controls the supply of pressure medium to the valve element 14. Inthe case illustrated, the movable piston element 15 is guided in apressure chamber 19 which can be charged with pressure medium. For thepurpose of carrying out the filling as rapidly as possible, means 26 forproducing an influencing pressure on the operating material situated inthe operating material sump 3 are provided. Said means comprise a valvedevice 30 for coupling the atmosphere 15 or a pressure medium connectionin the form of a pressure medium source 28 to the operating material inthe operating material sump 3. This valve device 30 is also assigned anactuating device 34. In the case illustrated, the valve device 30comprises a further piston element 20 which is arranged in the pressurechamber 19, forms a valve element and is prestressed in its position bymeans of a spring device 21. The spring force of the spring device 21 isdirected counter to the pressure force in the pressure chamber 19 whenbeing charged with pressure. In the case illustrated of a particularlycompact and therefore advantageous design, the means 6 and the means 26are functionally and structurally coupled to one another, withindividual components of both systems being used, for example the valvedevice 18 as actuating device 17 and 34, and also the common pressurespace 19 and the coupling to the atmosphere 25. As illustrated for thevalve devices 30 and 13, these components are preferably combined toform a structural unit 35.

[0017] The movable piston element 15 is preferably likewise assigned aspring device 22 which acts counter to the movement of the pistonelement 15. In the unpressurized state of the entire system, asillustrated in FIG. 1, the spring device 22 is relieved of load. In thisstate, the device 12 for the closure of the opening 11, i.e. the controlvalve 13, is in the opened state. The valve element 14 does not interactwith the valve seat 16. There is the possibility of operating materialoverflowing from that region of the operating material reservoir 2 whichis present above the operating material sump 3, in particular thepossibility of leakage oil flowing in, the inflow direction of which isindicated by 23 a, of operating material flowing back from thehydrodynamic element, the flow direction of which is referred to by 23b, and of the overflow of directly returned operating material accordingto 23 c from that region 24 of the operating material reservoir 2 whichis situated outside the closable operating material sump and is alsopartially filled with operating material. The two pistons, the pistonelements 20 and 15 of the valve devices 13 and 30 combined to form thestructural unit 35 in the form of a combined valve device 31, are in thestate in which they are relieved of load, i.e. in the unpressurizedstate. In this state, the pressure medium connection 25, which isdesigned as air connection, is decoupled from the pressure chamber 19.The control valve 13 is situated as it were in its first functionalposition I. In a similar manner thereto, the valve device 30 [lacuna]also in I′. The final functional position II of the valve element 14 andII″ of the valve element 20, which position is to be taken up when theopening 11 is closed, are illustrated in FIG. 2. With reference thereto,the function of the closable operating material sump 3 during theclosing process is depicted schematically. The basic construction of theoperating material supply device 1 corresponds to that described in FIG.1 and so the same reference numbers are used for identical elements. Theillustration according to FIG. 2 differs merely with regard to thefunctional position II of the valve element 14 of the control valve 13in comparison with the functional position I in FIG. 1.

[0018] In order to close the operating material sump 3, the controlvalve 13, in particular the movable piston element 15, is charged withpressure. This pressure is supplied via the valve device 18 in thepressure chamber 19. In this case, compressed air supplied to thepressure space 19 via the valve device 18 when leaving the pressurizedstate is used for displacing the piston element 15 in order to close thecontrol valve 13 by interaction with the valve seat 16. During closureof the opening 11, the leakage losses arising during operation areblocked [lacuna] the return movements of the individual elements, eitherthe return movements directly of the switching elements. Furthermore, itis, however, required, for the purpose of filling the switchingelements, to supply the latter with operating material from theoperating material sump 3. This takes place via the filling line 4,with, for the purpose of the filling operation being as rapid aspossible, means 26 for producing an influencing pressure on theoperating material in the operating material sump 3 being provided.After closure of the opening 11, the operating material sump 3 ispressure-tight with respect to the remaining region 24 of the operatingmaterial reservoir 2 or of the corresponding housing which forms thehousing 5 of the operating material reservoir. The means 26 furthermorecomprise a pressure line 27 which extends into the operating materialsump 3 and is coupled to a pressure medium source 28, here theatmosphere. In the case illustrated here, the means 26 for producing aninfluencing pressure and the pressure-tight closure of the operatingmaterial sump 3 with respect to the environment or a housing interiorare preferably formed by a unit. The valve device 18, which acts as anactuating device 17, is, in order to charge the pressure chamber 19 soas to bring about a movement of the piston element 15, used at the sametime as actuating device for actuation of the valve device 30, inparticular of the second piston element 20, which permits or blocks acoupling between the pressure medium connection and the operatingmaterial sump, so as to couple a pressure medium source 28 or theatmosphere to the operating material sump 3.

[0019] In FIG. 2, the piston element 20 has a functional position II′ inwhich the pressure medium connection 25 leads merely into the pressurechamber 19 and which blocks the transfer of the pressure medium from thepressure chamber 19 into the operating material sump 3. The combinedvalve device 31 is thus used not only merely for closing the operatingmaterial sump 3, but at the same time also for controlling theinfluencing pressure on the operating material sump 3. This designtherefore constitutes a particularly compact constructional unit with avery small number of individual elements. There is theoretically alsothe possibility of separating this function, but this results in anincreased number of parts and in an increased outlay on control.

[0020]FIG. 3 illustrates the third functional state which is referred toby III, for the valve element 14 for closing the opening 11, and byIII′, for the second piston element for releasing the connection betweenthe pressure medium connection 28 and the atmosphere 25 and operatingmaterial sump 3. Since the operating material sump 3 is arranged belowthe conventionally arising operating material level, in particular thefunctioning material level 7 in the operating material reservoir 2, theoperating material sump 3 is, as a rule, always filled with operatingmaterial. In this case, pressure medium flowing in, for example merelyair flowing in via the pressure medium connection 25, immediately bringsabout an increase in the operating material pressure in the operatingmaterial sump 3 without the dead volume in the operating material sumphaving to be sealed. The operating material pressure thus producedresults in the operating material being transported out of the operatingmaterial sump 3 via the filling line 4 to the switching element. Theremaining part of the operating material reservoir 2, i.e., inparticular, the region 24 partially filled with operating material,[lacuna] outside the spatial dimensions of the operating material sump.As soon as the filling operation is finished, the pressure mediumconnection 26, in particular the supply of air, is switched off and thecompressed air in the operating material sump 3 can escape via thenonreturn valve device 29 arranged there by way of the coupling to therest of the interior, in particular into the vented part of the housing,i.e. region 24, and can pass on from there into the atmosphere, with theresult that the individual piston elements—the piston element 20 andpiston element 15—are displaced again into the position I or I′ aimedfor in the unpressurized state, and the connection between the operatingmaterial sump and the remaining region 24 of the operating materialreservoir is produced again. The leakage oil or operating materialcollected in the meantime in the vented region 24 of the operatingmaterial reservoir can flow back into the operating material sump viathe opening 11 which has now been released again. Another variantconsists in turning the flowing back operating material into theoperating material sump 3 directly via nonreturn valves.

[0021] The solution according to the invention is based on enablingrapid filling of switching elements in gearing assemblies, startingunits, retarder units or the like. In this case, the operating materialrequired for the filling operation from an operating material sump of anoperating material reservoir 2 is used, with the latter being placedunder pressure for filling purposes. However, this presupposes that theoperating material sump 3 can be closed in a pressure-tight manner withrespect to the atmosphere or the rest of the interior of the operatingmaterial reservoir 2. Furthermore, corresponding means for supplying orproducing an influencing pressure on the operating material sump, whichhas been closed in a pressure-tight manner, are required. In this case,the two functions—pressure-tight closure of the operating material sump3 and production or provision of an influencing pressure and charging ofthe operating material sump 3 with the latter are carried out bydifferent devices. In a particularly advantageous design according toFIGS. 1 to 3, use is made, however, for this purpose of a control valvedevice having corresponding line connections. The carrying out of thisfunction, in particular the setting of the corresponding valve position,is obtained by the corresponding dimensioning of the forces acting onthe valve piston elements 20 and 15 via the spring devices and by thedesign of these pistons and the dimensioning thereof. Other designs arelikewise conceivable. List of reference numbers  1 Operating materialsupply device  2 Operating material reservoir  3 Operating material sump 4 Filling line  5 Housing  6 Means for the pressure-tight closure ofthe operating material sump with respect to the surroundings or thehousing interior  7 Functioning material level  8 Housing region  9Chamber 10 Upper boundary wall 11 Opening 12 Device for closing theopening 11 13 Control valve 14 Valve element 15 Movable piston element16 Valve seat 17 Means for actuating the valve element 18 Valve device19 Pressure chamber 20 Piston element 21 Spring device 22 Spring device23a, 23b, 23c Inflow direction 24 Region which can be partially filledwith operating material and is situated outside the operating materialsump 25 Pressure medium connection 26 Means for charging the operatingmaterial sump with an influencing pressure 27 Pressure line 28 Pressuremedium source 29 Nonreturn valve device 30 Valve device 31 Combinedvalve device 32 Housing 33 Housing interior 34 Actuating device 35Constructional unit 36 Suction line

1. An operating material supply device (1) for hydro-dynamic components,in particular for hydrodynamic switching elements in starter units,retarder units or gearing assemblies, 1.1 having an operating materialreservoir (2) which is arranged in a housing and comprises an operatingmaterial sump (3); 1.2 having at least one filling line (4) whichconnects the operating material sump (3) to the hydrodynamic component;characterized by the following feature: 1.3 the operating material sump(3) can be closed in a pressure-tight manner.
 2. The operating materialsupply device (1) as claimed in claim 1, characterized by the followingfeatures: 2.1 the operating material sump (3) is arranged in the lowerregion of the operating material reservoir (2); 2.2 the operatingmaterial sump (3) is delimited from the remaining area of the operatingmaterial reservoir (2) by housing walls and is connected to the space ofthe operating material reservoir (2) outside the operating material sump(3) via at least one opening (11).
 3. The operating material supplydevice (1) as claimed in either of claims 1 and 2, characterized in thatthe operating material reservoir (2) is arranged in the housing in thestarting unit, retarder unit or gearing assembly.
 4. The operatingmaterial supply device (1) as claimed in one of claims 1 to 3,characterized in that the closable operating material sump (3) isassigned means (26) for charging it with an influencing pressure (26).5. The operating material supply device (1) as claimed in claim 4,characterized in that means (6) for the pressure-tight closing of theoperating material sump (3) with respect to the surroundings or thehousing interior are functionally coupled to the means (26) for chargingthe operating material sump (3) with an influencing pressure.
 6. Theoperating material supply device (1) as claimed in either of claims 4 or5, characterized in that means (6) for the pressure-tight closing of theoperating material sump (3) are structurally coupled to the means (26)for subjecting the operating material sump (3) to an influencingpressure.
 7. The operating material supply device (1) as claimed in oneof claims 4 to 6, characterized in that the means (6) for thepressure-tight closure of the operating material sump (3) and the means(26) for charging the operating material sump to an influencing pressureare at least partially combined in a constructional unit.
 8. Theoperating material supply device (1) as claimed in one of claims 1 to 7,characterized by the following features: 8.1 the means (6) for thepressure-tight closure of the operating material sump with respect tothe surroundings or the housing interior comprise at least one controlvalve (13); 8.2 the control valve (13) comprises at least one valveelement (14) which interacts with a valve seat (16), which is formed bythe element forming the opening (11), and a movable piston element (15)which is coupled to the valve element (14); 8.3 the control valve (13)is coupled to an actuating device (17) for actuating the valve element(14).
 9. The operating material supply device (1) as claimed in claim 8,characterized in that the actuating device (17) is coupled to a pressuremedium connection (25, 28).
 10. The operating material supply device (1)as claimed in one of claims 1 to 9, characterized in that the means (26)for producing an influencing pressure comprise a valve device (30)which, when charged via an actuating device (34), connects a pressuremedium source (28) or a connection to the atmosphere (25) to theoperating material sump (3).
 11. The operating material supply device(1) as claimed in one of claims 2 to 9, characterized in that thecontrol valve (13) of the means for the pressure-tight closure (6) andthe valve device (30) of the means (26) for charging the operatingmaterial sump (3) so as to couple the atmosphere (25) or a pressuremedium source (28) to the operating material sump (3) are combined in acombined valve device (31), and the actuating device (17, 34) for thecontrol valve (13) and the valve device (30) is formed by an actuatingdevice assigned jointly to both.
 12. The operating material supplydevice (1) as claimed in claim 11, characterized by the followingfeatures: 12.1 the combined valve device (31) comprises at least onepressure space (19) in which the valve element (14) of the control valve(13) and the valve element (20) of the valve device (30) are arrangedand mounted displaceably; 12.2 with a pressure medium connection (25) tothe atmosphere or to a pressure medium source (28); 12.3 with a furthersecond connection (27) to the operating material sump (3).
 13. Theoperating material supply device (1) as claimed in claim 12,characterized in that the valve elements (14, 20) of the valve device(30) of the means (26) and of the control valve (13) are kept in aprestressed position in the pressureless state of the pressure space(19) by means of spring devices (21, 22), and the spring device andvalve elements (14, 20) of the valve device (30) of the means (26) andof the control valve (13) are dimensioned in such a manner that thecharging of the operating material sump (3) takes place automatically assoon as the operating material sump is closed.
 14. The operatingmaterial supply device (1) as claimed in one of claims 1 to 13,characterized in that the housing walls (8, 10) of the operatingmaterial sump (3) is formed by the housing (32) of the hydrodynamiccomponent.
 15. The operating material supply device (1) as claimed inone of claims 1 to 14, characterized in that the housing walls (8, 10)of the operating material sump (3) are formed by the housing of thestarting unit.
 16. The operating material supply device (1) as claimedin one of claims 1 to 14, characterized in that the housing walls (8,10) of the operating material sump (3) are formed by the housing of agearing assembly and/or retarder unit assigned to the hydrodynamiccomponent.
 17. Use of an operating material supply device (1) as claimedin one of claims 1 to 16 in a closed circuit assigned to thehydrodynamic component.
 18. Use of the operating material supply device(1) as claimed in one of claims 1 to 16 in a vehicle.
 19. Use of anoperating material supply device (1) as claimed in of claims 1 to 16 ina stationary system.